Device for rendering a pulley tight or loose upon a shaft



(No Model.)

G. DRYDEN.

DEVICE FOR RENDBRING A 'PULLEY T IGHT v OR. LOOSE UPON A SHAFT No. 252,086. Patented Jan; 10,1882.

N. PETERS. Pholwl ithngnpbar, Waihinghm, D. Q

a UNITED STATES PATENT OFFICE.

"GEORGE DRYDEN, or BOSTON, MASSACHUSETTS.

'DEVlCE FOR RENDERING A PU LLEY TIGHT R LOOSE UPON SHAFT.

SPECIFICATION forming part of Letters Patent No. 252,036, dated January 10, 1882. Application filed October 17, 1881. (No model.)

Toall whom t'tmety concern:

Be itknown that I, GEORGE DRYDEN, of

Boston, in the county of Suffolk and State of Massachusetts, have invented a new and use ful improved device for rendering the same pulley practically tight or loose upon a shaft at will, of which the following is a specification.

My invention is principally of value in reversing elevating machinery for running elevators in buildings, and is shown in the drawings as applied to such elevatingmachinery; but it may be applied in place of the ordinary tight and loose pulleys whenever and wherever practicable.

My invention may be described as follows, reference being bad to the accompanying drawings, which form a part of this specification.

Figure l of the drawings is a view in per-v spective of my invention as applied to elevating machinery. Fig. 2 is alrelevatioli'in part section, (several of the important portions of the inventionbeing in section,) which section is cut on the line w of Fig. 3, and 3 presents a view in perspective of those leading features of the invention which are in sectionin Fig. 2.

Like letters of reference indicate like parts in the different figures of the drawings.

The invention consists in one upward pulley and one downward pulley placed loose upon the worm-shaft of an elevating-machine. Over the periphery of the hub of each of said pulleys is placed a spring, said spring being covered by a sleeve, which sleeve fits over and around said spring and is fast to thewormshaft. The spring passes around over said'hub and within sald sleeve, the two ends of the spring passing through the sleeve and forming two lips, a lever-bar with a tapering slot at one end thereof, and with the pivot forming the fulcrum attached to the sleeve. A loose tapering sleeve with an annular slot at the center' thereof is placed upon the worm-shaft. An eccentric is placed upon the shippingshaft,

the eccentric-rod connecting, by means of an ordinary cross-head, with an oscillating lever,

which lever is provided with a stud, said stud being placed in said annular slot,'so that by pulling the shipping cord in the car, which cord is attached to the end of the shippingshafr, the tapering grooved sleeve is moved to and fro on the worm-shaft, and as said sleeve is passed under the end of the lever bar opposite to the slotted end thereof, said opposite end being thereby raised, the tapering slot in the lever-bar is pressedvdown over the two lips of the spring, thereby pressing said lips to getherand tightening said spring around said pulley-hub, and thereby] making the pulley tight, all to be constructed and operatedin a manner to be hereinafter fully described.

A represents the worm-shaft of an elevating machine. B is the upward belt-pulley, and B thedownward belt-pulley. The downward pul ley is equipped in the same manner as is the upward pulley, in connection with which latter the invention is fully illustrated'iu the drawings. The hubs b ofthe two pulleys B and B are loose upon the worm-shalt. A spring, 0, is fitted easily around the periphery of each pulley-hub, so that said huh can. when thedevice is in the position shown by the drawings, revolve within said spring. The two ends a and c of the spring are carril d up through the sleeve I), forming lips, as clearly shown in Fig. 3, said sleeve b.fitting over the spring 0,. as shown. The sleeve I), however, is keyed held by the pivot 0 which pivot forms the futcrum of said lever. In the lever (J, and near the end thereof is the slot (1, which slot tapers as it passes inward, being smaller at the inside than at the outside end thereof, as shown in the drawings. c

The sleeve D is loose upon the worm-shaft A, and tapers both ways from its center, as shown in Fig. 1. Said sleeve is provided with the annular slot 6, said slot passing completely around said sleeve.

The eccentric H is placed upon the shippingsha-tt J in the usual manner and the ecceu tricrod G is pivoted to the cross head 9 in the ordinary manner, as shown in Fig. 1.- The oscillating lever F is also pivoted to the cross-head g, and is provided with a stud,f, which stud is inserted in the annular slot or groove e, all of which is shown in Fig. l. The shippingeord, which is controlled by the boy running the elevator-car, is attached to the shippingshat't J at the end thereofin the usual manner.

Having described theconstruction of my new device and its application to elevating machin- -B and B are running loose.

ery, I will describe its operation as follows: The drawings show theinvention in what may be called its normal position --that is to say, itis shown in the position occupied when theclevator-caris not in motion and both the pulleys It is now desired, for example, to move the car upward. The boy in charge pulls the shippingcord and turns the Shipping-shaft J so as to throw the eccentric H back. This, as is obvious from an' examination of the drawings, moves the end of the oscillating lever F, which is inserted in the annular slot 0 by means of the stud f, in the opposite direction, running-one end of the loose tapering sleeve D under the end of the lever O; and it is obvious that at the same time the opposite end of'said lever is lowered, pressing the tapering slot d down over the lips 0 and c of the spring 0, thus pinching said lips more and more tightly together until the ends of the lips touch the inner end of the slot. The spring 0 is thus bound tightly around the periphery of the pulley-hub b and as the two lips c and c are held in the sleeve 1), and said sleeve bis keyed fast to the worm-shalt A, and the lever O is held between the lips 0, which lips form a part of the sleeve b, it is readily seen that the pulley B is made practically tight upon the worm-shaft, and the worm-shaft is made to turn thereby, as said pulley is connected with the source of power by means of the belt M. When the car is to be run downward the shipping-cord is pulled so as to turn the shipping-shaft J in the opposite direction, carrying the eccentric H forward, thus throwing the cross-head g, and with it the oscillating lever F, forward, as shown by dotted lines in Fig. 1, and running the loose sleeve D under the end of the lever G, which lever corresponds with the opposite lever, 0, before described. The downward pulley B is made 7 practically tight in the same manner, and the worm-shaft A is turned so as to move the car downward.

It is hardly necessary to state that the crossed belt N (seen in Fig. 1) is the downward belt.

Having thus described my invention and the manner of carrying the same into effect, what I claim as new, and desire to secure by Letters Patent, is-

1. In an elevating-machine, the mode of renderin g a pulley practically tight upon a shaft and in turn loosening the same by means ot'a spring carried around over the periphery of the pulley-hub and inside ofa sleeve, which sleeve is keyed fast upon said shaft, the two ends of said spring holding it firmly in and to said O and G, with tapering slots (1, the worm-shaft A, the tapering loose sleeve D, with annular slot 6, the oscillating lever F, provided with the stud f, the cross-head g, the eccentric H, with eccentric-rod G, and the shipping-sh aft J, operated by the shipping-cord, all constructed and arranged substantially as described, and for the purpose set forth.

GEORGE DRYDEN.

Witnesses CHARLES H. BARROWS, FRANcis M. BoU'rWELL. 

